libs/lmo/src/lmo_lualib.c

   1 /*
   2  * lmo - Lua Machine Objects - Lua binding
   3  *
   4  *   Copyright (C) 2009 Jo-Philipp Wich <xm@subsignal.org>
   5  *
   6  *  Licensed under the Apache License, Version 2.0 (the "License");
   7  *  you may not use this file except in compliance with the License.
   8  *  You may obtain a copy of the License at
   9  *
  10  *      http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  *  Unless required by applicable law or agreed to in writing, software
  13  *  distributed under the License is distributed on an "AS IS" BASIS,
  14  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  *  See the License for the specific language governing permissions and
  16  *  limitations under the License.
  17  */
  18
  19 #include "lmo_lualib.h"
  20
  21 extern char _lmo_error[1024];
  22
  23
  24 static int lmo_L_open(lua_State *L) {
  25         const char *filename = luaL_checklstring(L, 1, NULL);
  26         lmo_archive_t *ar, **udata;
  27
  28         if( (ar = lmo_open(filename)) != NULL )
  29         {
  30                 if( (udata = lua_newuserdata(L, sizeof(lmo_archive_t *))) != NULL )
  31                 {
  32                         *udata = ar;
  33                         luaL_getmetatable(L, LMO_ARCHIVE_META);
  34                         lua_setmetatable(L, -2);
  35                         return 1;
  36                 }
  37
  38                 lua_pushnil(L);
  39                 lua_pushstring(L, "out of memory");
  40                 return 2;
  41         }
  42
  43         lua_pushnil(L);
  44         lua_pushstring(L, lmo_error());
  45         return 2;
  46 }
  47
  48 static int lmo_L_hash(lua_State *L) {
  49         const char *data = luaL_checkstring(L, 1);
  50         uint32_t hash = sfh_hash(data, strlen(data));
  51         lua_pushnumber(L, hash);
  52         return 1;
  53 }
  54
  55 static int _lmo_lookup(lua_State *L, lmo_archive_t *ar, uint32_t hash) {
  56         lmo_entry_t *e = ar->index;
  57
  58         while( e != NULL )
  59         {
  60                 if( e->key_id == hash )
  61                 {
  62                         lua_pushlstring(L, &ar->mmap[e->offset], e->length);
  63                         return 1;
  64                 }
  65
  66                 e = e->next;
  67         }
  68
  69         lua_pushnil(L);
  70         return 1;
  71 }
  72
  73 static int lmo_L_get(lua_State *L) {
  74         lmo_archive_t **ar = luaL_checkudata(L, 1, LMO_ARCHIVE_META);
  75         uint32_t hash = (uint32_t) luaL_checknumber(L, 2);
  76         return _lmo_lookup(L, *ar, hash);
  77 }
  78
  79 static int lmo_L_lookup(lua_State *L) {
  80         lmo_archive_t **ar = luaL_checkudata(L, 1, LMO_ARCHIVE_META);
  81         const char *key = luaL_checkstring(L, 2);
  82         uint32_t hash = sfh_hash(key, strlen(key));
  83         return _lmo_lookup(L, *ar, hash);
  84 }
  85
  86 static int lmo_L_foreach(lua_State *L) {
  87         lmo_archive_t **ar = luaL_checkudata(L, 1, LMO_ARCHIVE_META);
  88         lmo_entry_t *e = (*ar)->index;
  89
  90         if( lua_isfunction(L, 2) )
  91         {
  92                 while( e != NULL )
  93                 {
  94                         lua_pushvalue(L, 2);
  95                         lua_pushinteger(L, e->key_id);
  96                         lua_pushlstring(L, &(*ar)->mmap[e->offset], e->length);
  97                         lua_pcall(L, 2, 0, 0);
  98                         e = e->next;
  99                 }
 100         }
 101
 102         return 0;
 103 }
 104
 105 static int lmo_L__gc(lua_State *L) {
 106         lmo_archive_t **ar = luaL_checkudata(L, 1, LMO_ARCHIVE_META);
 107
 108         if( (*ar) != NULL )
 109                 lmo_close(*ar);
 110
 111         *ar = NULL;
 112
 113         return 0;
 114 }
 115
 116 static int lmo_L__tostring(lua_State *L) {
 117         lmo_archive_t **ar = luaL_checkudata(L, 1, LMO_ARCHIVE_META);
 118         lua_pushfstring(L, "LMO Archive (%d bytes)", (*ar)->length);
 119         return 1;
 120 }
 121
 122
 123 /* method table */
 124 static const luaL_reg M[] = {
 125         {"close",       lmo_L__gc},
 126         {"get",         lmo_L_get},
 127         {"lookup",      lmo_L_lookup},
 128         {"foreach",     lmo_L_foreach},
 129         {"__tostring",  lmo_L__tostring},
 130         {"__gc",        lmo_L__gc},
 131         {NULL,          NULL}
 132 };
 133
 134 /* module table */
 135 static const luaL_reg R[] = {
 136         {"open",        lmo_L_open},
 137         {"hash",        lmo_L_hash},
 138         {NULL,          NULL}
 139 };
 140
 141 LUALIB_API int luaopen_lmo(lua_State *L) {
 142         luaL_newmetatable(L, LMO_LUALIB_META);
 143         luaL_register(L, NULL, R);
 144         lua_pushvalue(L, -1);
 145         lua_setfield(L, -2, "__index");
 146         lua_setglobal(L, LMO_LUALIB_META);
 147
 148         luaL_newmetatable(L, LMO_ARCHIVE_META);
 149         luaL_register(L, NULL, M);
 150         lua_pushvalue(L, -1);
 151         lua_setfield(L, -2, "__index");
 152         lua_setglobal(L, LMO_ARCHIVE_META);
 153
 154         return 1;
 155 }